CVE-2020-37268
Print Assumptions does not report that a definition was produced while universe checking was disabled when that definition reaches the caller through Parameter Inline in a module type. Applying a functor inlines the body of the parameter, and the inlining drops the record that the term was built under Unset Universe Checking, so the resulting constant carries no trace of the unsafe operation. A module implementation can therefore prove False using a universe inconsistency, expose it through an inlined parameter, and have Print Assumptions report the dependent proof as closed under the global context. Because Print Assumptions is the in-process audit used to confirm that a development rests on no unexpected assumptions, a dependency built this way passes that audit while proving arbitrary propositions. The standalone checker coqchk does reject the resulting compiled file. The project records this in dev/doc/critical-bugs.md under non-fixed bugs and rates the risk as moderate when coqchk is not used.
What this means for your business
- An attacker can use it only with access to the machine itself, without a login, but only after tricking someone into an action such as opening a file or a link.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 6.3 (v3.1)
- Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N- CVSS v4
- 6.8
- Weakness
- CWE-778
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-08-24
- Last modified
- 2026-09-08
- Sources
- NVD
References
- https://github.com/endrazine/rocq-cve-poc-12155
- https://github.com/rocq-prover/rocq
- https://github.com/rocq-prover/rocq/blob/master/dev/doc/critical-bugs.md
- https://github.com/rocq-prover/rocq/issues/12155
- https://www.vulncheck.com/advisories/coq-and-rocq-prover-print-assumptions-omits-unsafe-universe-checking-inlined-through-parameter-inline
- https://github.com/rocq-prover/rocq/issues/12155